I was sitting on my deck. I looked up as an airliner was going over the usual landing path in our area went overhead.

Next to the airliner I saw an object. It was oval & dark, maybe dark due to the time of night. I watched the airliner pass it.

Then I focused on the object. It was rocking back and forth, left to right.

I called to my daughter who was just inside the door. She came out and saw it too. We watched it as it traveled towards the west, still rocking from side to side.

It went into a thin hazy cloud and my daughter said "maybe it's a weather balloon". It was traveling slowly and I asked my daughter, "why would a weather balloon be rocking from side to side?", then it came out from the thin hazy cloud, went a little bit further (I also need to mention that the whole time it was traveling slowly) then all of a sudden it made a sharp left turn into denser clouds and then it was gone.